STUDY ON CHEMICAL CONSTITUENTS OF ESSENTIAL OIL FROM THYMUS MONGOLICUS RONN. Determination of carvacrol and thymol in Mosla chinensis by HPLC STUDIES ON THE COMPONENTS OF ESSENTIAL OILS FROM ELSHOLTZIA SPLEDENS NAKAI EX F MAEKAWA Monoterpenoids from whole plants of Carpesium macrocephalum Studies and Comparisons on Chemical Components of Essential Oils from Clematis hexapetala Pall. and Inula nervosa Wall.